Deep in the rain forest of Ecuador lives a frog that just can't seem to make up its mind. The amphibian can be covered in spikes one moment and totally smooth the next! Dubbed the "punk rocker" frog, it's the first vertebrate—or an animal with a backbone—known to change its skin texture.

On a nighttime walk in 2009, scientist Katherine Krynak spotted a well-camouflaged, marble-size amphibian that was covered in spines. But when she brought it inside, suspecting it was a new species,Krynak found a rather smooth and slimy critter.

"I was so mad at myself!" Krynak says. "I thought I had brought back the wrong frog."

But she hadn't. When she tucked a small piece of moss in the frog's container to make it more comfortable before releasing it back into the forest, the spines slowly reappeared.

"It was shocking," she says. It took Krynak and colleagues years to gather enough information to prove it was a new species. Now the frog finally has an official name: the mutable rainfrog.

Scientists aren't sure how the frog forms these spines so quickly, or what the spikes are made of. But they do think the shifting skin texture might be a form of camouflage to help the animal blend into mossy environments. Talk about a smooth transition!

Text from "Shape-Shifting Frog Found, Goes From Spiky to Smooth in Minutes" by Carrie Arnold for National Geographic News